Invisible Emergency Lighting for an Aircraft Cabin

ABSTRACT

Emergency cabin illumination for an aircraft, comprising: at least one cabin component ( 2, 10, 20, 30 ) of an aircraft and at least one emergency lighting means ( 6, 16, 22, 34 ), the at least one emergency lighting means ( 6, 16, 22, 34 ) being arranged in or on the cabin component ( 2, 10, 20, 30 ) so that the emergency lighting means ( 6, 16, 22, 34 ) in its switched-off state has no contrast to its environment, and in the switched-on state of the emergency lighting means ( 6, 16, 22, 34 ) the light which it emits emerges from or on the cabin component ( 2, 10, 20, 30 ).

The invention relates to an emergency cabin illumination for anaircraft, such that when it is switched off, a passenger in the aircraftcannot recognise it as emergency illumination.

Emergency illumination for a cabin of an aircraft is mandatorilyprescribed, to illuminate the cabin in an emergency, e.g. to clear thecabin rapidly. It must be possible to operate the emergency illuminationindependently of other illumination equipment.

In cabins of the prior art, autonomous, separately installed and/ordeveloped emergency illumination devices are used. These emergencyillumination devices are, for instance, arranged on the overhead bins ofa cabin. The emergency illumination devices are distributed through thecabin, visible to a passenger, and contribute to an uneasy appearance ofthe cabin as seen by the passenger. The inventors have also recognisedthat for sensitive passengers, an emergency illumination device has apsychological effect which should not be underestimated, since itconfronts passengers with the possibility of an accident.

U.S. Pat. No. 6,095,662 discloses a light arrangement with an emergencyillumination device with a first and second lamp and a transparentcover.

DE 298 09 772 U1 discloses a container unit for a lecture orpresentation room. The arrangement of seats in the container unitgenerally corresponds to that of aircraft seats in an aircraft. In themiddle of the ceiling, there is a continuous ventilation duct. In astainless steel ventilation grille of the ventilation channel,additional radiators for direct lighting are fitted.

DE 82 20 984 U1 teaches a plurality of illuminated plates and platesbetween them which can act as emergency lighting.

EP 0 261 811 A2 describes escape route markers which are arranged in thefloor of an aircraft.

WO 2005/094378 A2 describes a plurality of combinations of LEDs andreflectors, which can also be used as emergency lighting means.

It is an object of the invention to create emergency illumination whichis not recognised as such by a passenger.

An emergency illumination for an aircraft comprises at least one cabincomponent of an aircraft and at least one emergency lighting means. Theat least one emergency lighting means is arranged in or on the cabincomponent so that the emergency lighting means in its switched-off statehas no contrast to its surroundings and/or the cabin component, and inthe switched-on state of the emergency lighting means the light which itemits emerges from or on the cabin component. Because the emergencylighting means has no contrast to its surroundings and/or the cabincomponent, it cannot be detected by a passenger. Consequently, theemergency lighting means in its switched-off state is invisible to thepassenger. It is understood that the term “cabin component” here doesnot per se mean a known device for illuminating a cabin in an emergency,but includes a device which can also be arranged in the cabin foranother purpose. The term “no contrast” must be understood as meaningthat within the wavelength range which is visible to the human eye, andthe resolution capability of the human eye, no contrast results. Also,this term must be understood from the point of view of an aircraftpassenger.

The emergency lighting means can be arranged in a relatively dark place,such as between two components, so that for this reason it cannot beseen, i.e. it has no contrast.

In a cabin of an aircraft, at least one emergency illumination systemwith at least one emergency lighting means can be arranged. In theswitched-on state, the at least one emergency illumination systemgenerates a brightness of at least the value which the applicable safetyregulations prescribe, in particular about 0.54 lux, preferably about 1lux or more, at the height of an arm rest in a gangway of an aircraft.

The emergency lighting means can be an LED. LEDs have a relatively highlight output with small size, low heat output and a low powerconsumption relative to the light output, compared with incandescentlamps or halogen lamps. The emergency lighting means can include atleast one associated functional element, for instance a reflector, alight outlet or a fixing device.

The at least one emergency lighting means, in its switched-off state ina cabin which is illuminated for normal operation, has no contrast toits surroundings and/or the cabin component. In normal operation, thecabin of an aircraft is illuminated such that in the gangway of theaircraft, at the height of an arm rest, the resulting brightness isabout 100 lux.

It is thus understood that the emergency lighting means, in itsswitched-off state, has no contrast to its surroundings and/or the cabincomponent, even if the cabin is illuminated as is normal for a flightwith passengers. The cabin component can be a cabin illumination device,such as a reading lamp. Arranging the emergency lighting means in acabin illumination system is preferred, since a light outlet, e.g.diffusers, is already present in it.

However, the cabin component can also be part of a ventilation device,which feeds air into the cabin or away from it. The emergency lightingmeans can, for instance, be arranged between the slats or fins of an airoutlet or air inlet grille of such a ventilation device.

The cabin component can be spaced such a distance from another cabincomponent that between the cabin components there is an intermediatespace, in which the emergency lighting means is arranged. Betweenindividual components of a cabin, e.g. overhead bins, there aretypically intermediate spaces which can receive the emergency lightingmeans.

The at least one emergency lighting means can also be arranged betweenelements of a cabin component, e.g. ceiling cladding or similar.

The emergency cabin illumination can comprise a plurality of emergencylighting means, which are arranged on one emergency illumination unit,the emergency illumination unit being arranged on and/or between atleast two cabin components, such as ceiling cladding elements oroverhead bins, in such a way that the light of the emergency lightingmeans can enter the cabin between the ceiling cladding elements oroverhead bins. The plurality of emergency lighting means results inspecially homogeneous lighting. The plurality of emergency lightingmeans also provides redundancy.

The emergency lighting unit can comprise a plurality of light outlets,from which the light of the emergency lighting means can enter thecabin. It is thus possible to hide the emergency lighting means in theirswitched-off state specially well from passengers.

The emergency cabin lighting can have multiple emergency lighting means,which are supplied redundantly with current. For instance, two currentsources can be present, each of them supplying current to a set with atleast one emergency lighting means. However, providing more than twocurrent sources, each of them supplying current to a set with at leastone emergency lighting means, is also conceivable.

Each redundant set of power supply and at least one emergency lightingmeans can generate a brightness of the prescribed minimum value, inparticular about 0.54 lux at the height of the arm rest of an aircraftseat. Even if one set of power supply and at least one emergencylighting means fails, the prescribed minimum brightness is still presentin an emergency. If, for instance, two redundant sets of power supplyand at least one emergency lighting means are present, in an emergencydouble the value of the prescribed minimum brightness can be present inthe cabin. If one redundant set of power supply and at least oneemergency lighting means fails, the prescribed minimum brightness isstill present.

The emergency lighting means can preferably radiate down from above.This has the effect that a passenger looking in the natural direction isnot dazzled by the emergency lighting means. Further, the emergencylighting means per se also remains invisible to a passenger, providedthat the passenger does not look upward.

By using multiple emergency lighting means, homogeneous lighting of thecabin can be achieved.

The invention also concerns a method of producing emergency illuminationfor an aircraft, with the step of arranging an emergency lighting meansin or on a cabin component of the aircraft so that the emergencylighting means in its switched-off state has no contrast to itsenvironment and/or the cabin components, and in the switched-on state ofthe emergency lighting means the light which it emits emerges from or onthe cabin component.

The invention is now described in more detail with reference to theattached schematic drawings, in which:

FIG. 1 is a not to scale view of an emergency illumination system, inwhich emergency lighting means are arranged in a ventilation device,

FIG. 2 is a not to scale view of a first emergency illumination systemaccording to the invention, in which the emergency lighting means arearranged in a cabin illumination device,

FIG. 3 is a not to scale view of a second embodiment of the invention,in which an emergency lighting means is arranged in a cabin component,and

FIG. 4 is a not to scale view of a third embodiment of the invention, inwhich a plurality of emergency lighting means are arranged betweenelements of ceiling cladding.

FIG. 1 shows schematically a ventilation device 2 with multiple finsand/or slats 4, with which air is fed into or out of a cabin of anaircraft. Between the fins and/or slats 4, and shifted back from the airoutlet openings and air inlet openings of the ventilation device, aplurality of emergency lighting means 6, each in the form of an LED, arearranged. It is understood that the internal space of a ventilationdevice, compared with the cabin to be ventilated, is darker, since thecabin is illuminated in use, whereas the internal space of theventilation device is not illuminated, and furthermore the fins and/orslats 4 shade the light of the cabin illumination. Because the internalspace of the ventilation device 2 is dark, the emergency lighting means6 in it cannot be detected, since they have no contrast to theirenvironment.

In normal operation, the emergency lighting means 6 also have nocontrast to the ventilation device 2 and the fins and/or slats 4, i.e.they are invisible to a passenger.

In emergency, the emergency lighting means 6 are activated via anautonomous power supply (not shown), so that they emit light, whichenters the cabin through the intermediate spaces between the fins and/orslats 4 of a ventilation device 2. The emergency lighting means 6 onlybecome detectable by a passenger in this rare case.

FIG. 2 shows an emergency lighting means 16, which is arranged in acabin illumination device 10. The cabin illumination device 10 includesa lighting means 12, which can be a fluorescent tube, incandescent lampor halogen lamp, a reflector 14 and a diffuser disc formed as a lightoutlet 19. In the cabin illumination device 10, a plurality of emergencylighting means 16 in the form of LEDs are arranged on a supporting board18. The emergency lighting means 16 is independently and autonomouslysupplied with current by the lighting means 12. Because of the diffuserdisc 19, a passenger cannot detect the elements in a cabin lightingillumination device 10, whereby the emergency lighting means 16 have nocontrast to the other elements of the cabin illumination device and thecabin illumination device 10 as a whole, and are thus invisible to apassenger. Even if the light outlet 19 is not formed as a diffuser disc,a passenger cannot detect the switched-off emergency lighting means 16if the lighting means 12 is switched on, because the lighting means 12has such brightness that the passenger by looking directly into thecabin lighting device 10 is dazzled, so that the switched-off emergencylighting means 16 has no contrast to the cabin illumination device 10 orthe elements of the cabin illumination device 10.

If the emergency lighting means 16 are switched on by switching on theautonomous emergency power supply, they emit light which enters thecabin via the light outlet 19. A passenger detects that the emergencylighting means 16 are present only in this rare case.

The cabin illumination device can be a reading lamp or a radiator, whichis arranged on the ceiling of the aircraft. Multiple emergency lightingmeans can be provided. Multiple redundant sets of emergency power supplyand at least one emergency lighting means can be present. In this way,the safety of the emergency lighting is increased.

In this embodiment, the emergency lighting means is disguised in a“cabin illumination device”, so that in normal operation it is invisibleto a passenger. The expression “normal operation” means that noemergency exists.

FIG. 3 shows, schematically and not to scale, two overhead bins 20,which are arranged in the upper region of the cabin. Between theoverhead bins, according to the invention an emergency lighting means22, which can be in the form of an LED, is arranged. The emergencylighting means 22 is in an intermediate space between the two overheadbins. Because the intermediate space between the overhead bins is notilluminated, the emergency lighting means 22 has no contrast to itssurroundings, i.e. to the intermediate space between the overhead bins20 and the overhead bins 20 as such. At the lateral end of theintermediate space, a screen can be arranged, so that the intermediatespace is undetectable for a passenger if he looks laterally in thedirection of the overhead bins 20. If the emergency lighting means 22 isin the form of an LED, only a very small intermediate space between theoverhead bins 20 is required, so that a passenger is not aware of theintermediate space. At the lower end of the intermediate space, betweenthe overhead bins 20, a diffuser can also be arranged, so that apassenger is not aware of the intermediate space between the overheadbins 20.

If the emergency lighting means 22 is supplied with current via anautonomous power supply, the light which the emergency lighting means 22emits emerges from the intermediate space between the overhead bins 20and illuminates the cabin. A passenger of the aircraft detects that theemergency lighting means 22 are present only in this rare case.

FIG. 4 shows a plurality of emergency lighting means 34, which accordingto the invention are arranged between two ceiling cladding elements 32a, 32 b of ceiling cladding 30. Because the intermediate space betweenthe ceiling cladding elements 32 a, 32 b is not lit, the emergencylighting means 34 have no contrast to their environment, i.e. to theintermediate space between the ceiling cladding elements 32 a, 32 b andthe ceiling cladding elements 32 a, 32 b as such.

The present invention thus provides emergency cabin illumination with atleast one emergency lighting means, which in its switched-off state hasno contrast to its surroundings. The surroundings of the emergencylighting means can be a cabin component or a space on a cabin component.For the purpose of the invention, a plurality of elements in a cabin canalso be considered as one cabin component. For instance, the emergencylighting means can be arranged in ceiling cladding, which represents acabin component and consists of multiple elements.

Because the emergency lighting means in its switched-off state has nocontrast to its surroundings, the emergency lighting means is notdetected by a passenger in the cabin of the aircraft. Consequently, thepassenger is not unnecessarily confronted with the possibility of anaccident or emergency, so that the passenger feels safer in theaircraft. In an emergency, the light which the emergency lighting meansemits emerges from or on the cabin component, and thus illuminates thecabin so that a passenger can leave the cabin safely in an emergency.

1. Emergency cabin illumination for an aircraft, comprising at least oneemergency lighting means, wherein the emergency lighting means isarranged in an intermediate space between a first ceiling claddingelement and a second ceiling cladding element, and the emergencylighting means in its switched-off state has no contrast to itssurroundings, and in the switched-on state of the emergency lightingmeans the light which it emits emerges from the intermediate spacebetween the first and second ceiling cladding elements.
 2. Emergencycabin illumination for an aircraft, comprising at least one emergencylighting means, wherein the emergency lighting means is arranged in anintermediate space between a first overhead bin and a second overheadbin, and the emergency lighting means in its switched-off state has nocontrast to its environment, and in the switched-on state of theemergency lighting means the light which it emits emerges from theintermediate space between the first and second overhead bins. 3.Emergency cabin illumination according to claim 1, wherein the emergencylighting means comprises an LED.
 4. Emergency cabin illuminationaccording to claim 1, wherein the emergency cabin illumination generatesa brightness of at least the prescribed minimum value, in particularabout 0.54 lux, at the height of the arm rest of an aircraft seat. 5.Emergency cabin illumination according to claim 1, wherein a pluralityof emergency lighting means are arranged on one emergency illuminationunit, the emergency illumination unit being arranged on at least twoceiling cladding elements or overhead bins, in such a way that the lightof the emergency lighting means can enter the cabin between the ceilingcladding elements or overhead bins.
 6. Emergency cabin illuminationaccording to claim 5, wherein the emergency illumination unit comprisesa plurality of light outlets, from which the light of the emergencylighting means can enter the cabin.
 7. Emergency cabin illuminationaccording to claim 1, wherein the emergency cabin illumination comprisesa plurality of emergency lighting means, which are each redundantlysupplied with current.
 8. Emergency cabin illumination according toclaim 7, wherein each redundant set of power supply and a least oneemergency lighting means generates a brightness of at least theprescribed minimum value, in particular about 0.54 lux, at the height ofthe arm rest of an aircraft seat.
 9. Aircraft cabin illumination device,comprising a lighting means to light the cabin, at least one emergencylighting means, and a light outlet, through which the light emitted bythe lighting means and the at least one emergency lighting means enterthe cabin, the at lesast one emergency lighting means being suppliedwith current autonomously and independently of the lighting means. 10.Aircraft cabin illumination device according to claim 9, wherein thelight outlet comprises a diffuser.
 11. Aircraft cabin illuminationdevice according to claim 9, wherein the emergency lighting meanscomprises an LED.
 12. Aircraft cabin illumination device according toclaim 9, wherein the at least one emergency lighting means generates abrightness of at least the prescribed minimum value, in particular about0.54 lux, at the height of the arm rest of an aircraft seat. 13.Aircraft cabin illumination according to claim 9, wherein the emergencycabin illumination comprises a plurality of emergency lighting means,which are redundantly supplied with current.
 14. Aircraft cabinillumination according to claim 13, wherein each redundant set of powersupply and at least one emergency lighting means generates a brightnessof at least the prescribed minimum value, in particular about 0.54 lux,at the height of the arm rest of an aircraft seat.